The dolphin biosonar beam is focused in stages: validation of a vibroacoustic finite element model using bottlenose dolphin simulations

Vanessa Trijoulet, Ted Cranford, Petr Krysl

Research output: Contribution to conferenceSpeech

33 Citations (Scopus)

Abstract

Environmental concern about the potential impact of anthropogenic sounds on aquatic life has sparked increased interest in marine bioacoustics. Experiments with live organisms are difficult to conduct and require considerable resources. Computerize numerical modelling is economical, reduces the need to expose live animals, and increases our understanding of bioacoustic interactions. Computer models should always be validated by comparing their simulations against results gleaned from live organisms. We investigated toothed whale biosonar by developing a numerical model that simulates the vibroacoustic functions of the biosonar apparatus (Krysl et al. 2008). In order to validate this approach, we used a vibroacoustic finite element model to recreate sound production and acoustic beam formation in the bottlenose dolphin (Tursiops truncatus). The model is constructed from live and post-mortem dolphin CT scans, tissue property measurements, and custom software. The right and left dorsal bursae were assumed to be the sound sources (Cranford 1988, 1992). This model confirms several hypotheses from previous studies: (1) the shape of the skull plays a role in the formation of the sound beam; (2) the melon has a significant capacity to focus the transmitted beam; (3) focusing the sound beam apparently happens in a series of stages that include contributions from the skull, nasal diverticula, melon, and connective tissue structures. An unexpected result is that adjustments to the focus and direction of the sound beam can result from small (millimetre scale) changes in the relative position of the anterior and posterior bursa within each sound generation complex. A comparison of our results with those from live dolphin psychoacoustic experiments (Au et al. 1986) supports validation of our vibroacoustic model.

Conference

Conference28th Annual Conference of the European Cetacean Society
CountryBelgium
CityLiege
Period7/04/14 → …

Fingerprint

Tursiops truncatus
dolphin
dolphins
Finite Element Model
Acoustic waves
Bioacoustics
simulation
bioacoustics
Simulation
melons
skull
Tissue
diverticulum
Computerized tomography
organisms
Computer Model
aquatic organisms
Numerical Modeling
echolocation
sound

Keywords

  • bottlenose dolphins
  • finite element model
  • biosonar functional morphology
  • beam formation
  • sound production

Cite this

Trijoulet, V., Cranford, T., & Krysl, P. (2014). The dolphin biosonar beam is focused in stages: validation of a vibroacoustic finite element model using bottlenose dolphin simulations. 28th Annual Conference of the European Cetacean Society, Liege, Belgium.
Trijoulet, Vanessa ; Cranford, Ted ; Krysl, Petr. / The dolphin biosonar beam is focused in stages : validation of a vibroacoustic finite element model using bottlenose dolphin simulations. 28th Annual Conference of the European Cetacean Society, Liege, Belgium.
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abstract = "Environmental concern about the potential impact of anthropogenic sounds on aquatic life has sparked increased interest in marine bioacoustics. Experiments with live organisms are difficult to conduct and require considerable resources. Computerize numerical modelling is economical, reduces the need to expose live animals, and increases our understanding of bioacoustic interactions. Computer models should always be validated by comparing their simulations against results gleaned from live organisms. We investigated toothed whale biosonar by developing a numerical model that simulates the vibroacoustic functions of the biosonar apparatus (Krysl et al. 2008). In order to validate this approach, we used a vibroacoustic finite element model to recreate sound production and acoustic beam formation in the bottlenose dolphin (Tursiops truncatus). The model is constructed from live and post-mortem dolphin CT scans, tissue property measurements, and custom software. The right and left dorsal bursae were assumed to be the sound sources (Cranford 1988, 1992). This model confirms several hypotheses from previous studies: (1) the shape of the skull plays a role in the formation of the sound beam; (2) the melon has a significant capacity to focus the transmitted beam; (3) focusing the sound beam apparently happens in a series of stages that include contributions from the skull, nasal diverticula, melon, and connective tissue structures. An unexpected result is that adjustments to the focus and direction of the sound beam can result from small (millimetre scale) changes in the relative position of the anterior and posterior bursa within each sound generation complex. A comparison of our results with those from live dolphin psychoacoustic experiments (Au et al. 1986) supports validation of our vibroacoustic model.",
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Trijoulet, V, Cranford, T & Krysl, P 2014, 'The dolphin biosonar beam is focused in stages: validation of a vibroacoustic finite element model using bottlenose dolphin simulations' 28th Annual Conference of the European Cetacean Society, Liege, Belgium, 7/04/14, .

The dolphin biosonar beam is focused in stages : validation of a vibroacoustic finite element model using bottlenose dolphin simulations. / Trijoulet, Vanessa; Cranford, Ted; Krysl, Petr.

2014. 28th Annual Conference of the European Cetacean Society, Liege, Belgium.

Research output: Contribution to conferenceSpeech

TY - CONF

T1 - The dolphin biosonar beam is focused in stages

T2 - validation of a vibroacoustic finite element model using bottlenose dolphin simulations

AU - Trijoulet, Vanessa

AU - Cranford, Ted

AU - Krysl, Petr

PY - 2014

Y1 - 2014

N2 - Environmental concern about the potential impact of anthropogenic sounds on aquatic life has sparked increased interest in marine bioacoustics. Experiments with live organisms are difficult to conduct and require considerable resources. Computerize numerical modelling is economical, reduces the need to expose live animals, and increases our understanding of bioacoustic interactions. Computer models should always be validated by comparing their simulations against results gleaned from live organisms. We investigated toothed whale biosonar by developing a numerical model that simulates the vibroacoustic functions of the biosonar apparatus (Krysl et al. 2008). In order to validate this approach, we used a vibroacoustic finite element model to recreate sound production and acoustic beam formation in the bottlenose dolphin (Tursiops truncatus). The model is constructed from live and post-mortem dolphin CT scans, tissue property measurements, and custom software. The right and left dorsal bursae were assumed to be the sound sources (Cranford 1988, 1992). This model confirms several hypotheses from previous studies: (1) the shape of the skull plays a role in the formation of the sound beam; (2) the melon has a significant capacity to focus the transmitted beam; (3) focusing the sound beam apparently happens in a series of stages that include contributions from the skull, nasal diverticula, melon, and connective tissue structures. An unexpected result is that adjustments to the focus and direction of the sound beam can result from small (millimetre scale) changes in the relative position of the anterior and posterior bursa within each sound generation complex. A comparison of our results with those from live dolphin psychoacoustic experiments (Au et al. 1986) supports validation of our vibroacoustic model.

AB - Environmental concern about the potential impact of anthropogenic sounds on aquatic life has sparked increased interest in marine bioacoustics. Experiments with live organisms are difficult to conduct and require considerable resources. Computerize numerical modelling is economical, reduces the need to expose live animals, and increases our understanding of bioacoustic interactions. Computer models should always be validated by comparing their simulations against results gleaned from live organisms. We investigated toothed whale biosonar by developing a numerical model that simulates the vibroacoustic functions of the biosonar apparatus (Krysl et al. 2008). In order to validate this approach, we used a vibroacoustic finite element model to recreate sound production and acoustic beam formation in the bottlenose dolphin (Tursiops truncatus). The model is constructed from live and post-mortem dolphin CT scans, tissue property measurements, and custom software. The right and left dorsal bursae were assumed to be the sound sources (Cranford 1988, 1992). This model confirms several hypotheses from previous studies: (1) the shape of the skull plays a role in the formation of the sound beam; (2) the melon has a significant capacity to focus the transmitted beam; (3) focusing the sound beam apparently happens in a series of stages that include contributions from the skull, nasal diverticula, melon, and connective tissue structures. An unexpected result is that adjustments to the focus and direction of the sound beam can result from small (millimetre scale) changes in the relative position of the anterior and posterior bursa within each sound generation complex. A comparison of our results with those from live dolphin psychoacoustic experiments (Au et al. 1986) supports validation of our vibroacoustic model.

KW - bottlenose dolphins

KW - finite element model

KW - biosonar functional morphology

KW - beam formation

KW - sound production

M3 - Speech

ER -

Trijoulet V, Cranford T, Krysl P. The dolphin biosonar beam is focused in stages: validation of a vibroacoustic finite element model using bottlenose dolphin simulations. 2014. 28th Annual Conference of the European Cetacean Society, Liege, Belgium.